Initial Commit

.gitignore

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+bin/
+.output/
+.vscode/

.gitmodules

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+[submodule "libbpf"]
+	path = libbpf
+	url = https://github.com/libbpf/libbpf

LICENSE

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README.md

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+# pamspy -- Credentials Dumper for Linux
+
+`pamspy` leverage eBPF technologies to achieve an equivalent work of [3snake](https://github.com/blendin/3snake).
+
+It will track a particular userland function inside the PAM (Pluggable Authentication Modules) library, used by many critical applications to handle authentication like:
+* sudo
+* sshd
+* passwd
+* gnome
+* x11
+* and many other ...
+
+![Demo](.img/pamspy.gif)
+
+## How to launch?
+
+`pamspy` is built as a static binary without any dependencies, and available on the [release]() page.
+
+```
+Usage: pamspy [OPTION...]
+pamspy
+
+Uses eBPF to dump secrets use by PAM (Authentication) module
+By hooking the pam_get_authtok function in libpam.so
+
+USAGE: ./pamspy -p $(/usr/sbin/ldconfig -p | grep libpam.so | cut -d ' ' -f4) -d /var/log/trace.0
+
+  -d, --daemon=PATH TO OUTPUT CREDENTIALS
+                             Start pamspy in daemon mode and output in the file
+                             passed as argument
+  -p, --path=PATH            Path to the libpam.so file
+  -r, --print-headers        Print headers of the program
+  -v, --verbose              Verbose mode
+  -?, --help                 Give this help list
+      --usage                Give a short usage message
+  -V, --version              Print program version
+
+Mandatory or optional arguments to long options are also mandatory or optional
+for any corresponding short options.
+
+Report bugs to .
+
+```
+
+As `pamspy` rely on libpam, we have to set the path where libpam is installed on your distribution. To find where libpam is installed you can run the following command :
+
+```
+> /usr/sbin/ldconfig -p | grep libpam.so | cut -d ' ' -f4
+/lib/x86_64-linux-gnu/libpam.so.0
+```
+
+Once you get the path you can launch `pamspy` :
+
+```
+> ./pamspy -p /lib/x86_64-linux-gnu/libpam.so.0
+```
+
+An easy way to launch `pamspy` is to use the following command :
+
+```
+> ./pamspy -p $(/usr/sbin/ldconfig -p | grep libpam.so | cut -d ' ' -f4)
+```
+
+`pamspy` can also be started as a daemon by providing an output file where credentials will be written:
+
+```
+./pamspy -p $(/usr/sbin/ldconfig -p | grep libpam.so | cut -d ' ' -f4) -d /tmp/credentials
+```
+
+## How to build?
+
+To build the static binary, we need third-party program. For eBPF we need `clang` to compile the C code into eBPF CO-RE code.
+We also rely on `bpftool` to create a skeleton from ebpf program to include it in our userland program. Then we need also `libelf` to find the correct symbol in libpam.
+
+```
+sudo apt install make clang-11 gcc libelf-dev bpftool
+```
+
+Then just build!
+
+```
+git clone https://github.com/citronneur/pamspy --recursive
+cd pamspy/src
+make
+```
+
+## How does It works?
+
+`pamspy` will load a userland return probe eBPF program to hook the `pam_get_authtok` function from `libpam.so`. 
+PAM stands for "Pluggable Authentication Modules", and have a flexible design to manage a different kind of authentication on Linux.
+
+Each time an authentication process tries to check a new user, It will call `pam_get_authtok`, and will be here to dump the content of the critical secrets!
+
+Easy! Enjoy!
+
+## Credits and references
+
+Thanks to @blendin for 3snake tool !!!
+

src/Makefile

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+# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+OUTPUT := .output
+BIN := bin
+CLANG ?= clang-11
+LLVM_STRIP ?= llvm-strip-11
+BPFTOOL ?= /usr/sbin/bpftool
+LIBBPF_SRC := $(abspath ../libbpf/src)
+LIBBPF_OBJ := $(abspath $(OUTPUT)/libbpf.a)
+INCLUDES := -I$(OUTPUT)
+CFLAGS := -g -Wall
+ARCH := $(shell uname -m | sed 's/x86_64/x86/')
+
+# Get Clang's default includes on this system. We'll explicitly add these dirs
+# to the includes list when compiling with `-target bpf` because otherwise some
+# architecture-specific dirs will be "missing" on some architectures/distros -
+# headers such as asm/types.h, asm/byteorder.h, asm/socket.h, asm/sockios.h,
+# sys/cdefs.h etc. might be missing.
+#
+# Use '-idirafter': Don't interfere with include mechanics except where the
+# build would have failed anyways.
+CLANG_BPF_SYS_INCLUDES = $(shell $(CLANG) -v -E - </dev/null 2>&1 \
+	| sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }')
+
+ifeq ($(V),1)
+	Q =
+	msg =
+else
+	Q = @
+	msg = @printf '  %-8s %s%s\n'					\
+		      "$(1)"						\
+		      "$(patsubst $(abspath $(OUTPUT))/%,%,$(2))"	\
+		      "$(if $(3), $(3))";
+	MAKEFLAGS += --no-print-directory
+endif
+
+.PHONY: all
+all: pamspy
+
+.PHONY: clean
+clean:
+	$(call msg,CLEAN)
+	$(Q)rm -rf $(OUTPUT) $(APPS) $(BIN)
+
+$(OUTPUT) $(OUTPUT)/libbpf $(BIN):
+	$(call msg,MKDIR,$@)
+	$(Q)mkdir -p $@
+
+# Build libbpf
+$(LIBBPF_OBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(OUTPUT)/libbpf
+	$(call msg,LIB,$@)
+	$(Q)$(MAKE) -C $(LIBBPF_SRC) BUILD_STATIC_ONLY=1		      \
+		    OBJDIR=$(dir $@)/libbpf DESTDIR=$(dir $@)		      \
+		    INCLUDEDIR= LIBDIR= UAPIDIR=			      \
+		    install
+
+# Build BPF code
+$(OUTPUT)/pamspy.bpf.o: pamspy.bpf.c $(LIBBPF_OBJ) $(wildcard %.h) vmlinux.h
+	$(call msg,BPF,$@)
+	$(Q)$(CLANG) -g -O2 -target bpf -D__TARGET_ARCH_$(ARCH) $(INCLUDES) $(CLANG_BPF_SYS_INCLUDES) -c $(filter %.c,$^) -o $@
+	$(Q)$(LLVM_STRIP) -g $@ # strip useless DWARF info
+
+# Generate BPF skeletons
+$(OUTPUT)/pamspy.skel.h: $(OUTPUT)/pamspy.bpf.o
+	$(call msg,GEN-SKEL,$@)
+	$(Q)$(BPFTOOL) gen skeleton $< > $@
+
+# Build user-space code
+
+$(OUTPUT)/pamspy.o: pamspy.c $(wildcard %.h) $(OUTPUT)/pamspy.skel.h | $(OUTPUT)
+	$(call msg,CC,$@)
+	$(Q)$(CC) $(CFLAGS) $(INCLUDES) -c $(filter %.c,$^) -o $@
+
+$(OUTPUT)/pamspy_symbol.o: pamspy_symbol.c $(wildcard %.h) | $(OUTPUT)
+	$(call msg,CC,$@)
+	$(Q)$(CC) $(CFLAGS) $(INCLUDES) -c $(filter %.c,$^) -o $@
+
+# Build application binary
+pamspy: $(OUTPUT)/pamspy.o $(OUTPUT)/pamspy_symbol.o $(LIBBPF_OBJ) $(BIN) | $(OUTPUT)
+	$(call msg,BINARY,$@)
+	$(Q)$(CC) $(CFLAGS)  -o bin/$@ $(OUTPUT)/pamspy_symbol.o $(OUTPUT)/pamspy.o  $(LIBBPF_OBJ) -l:libelf.a -l:libz.a -static
+
+# Build helpers
+$(HELPERS):
+	$(call msg,BINARY,$@)
+	$(Q)$(CC) $(CFLAGS) $@.c -o bin/$@
+
+# delete failed targets
+.DELETE_ON_ERROR:
+
+# keep intermediate (.skel.h, .bpf.o, etc) targets
+.SECONDARY:
+